D-Day, or Operation Neptune, was the first move in Operation Overlord, the codename for the Battle of Normandy. Nine thousand Allied soldiers were killed or wounded, but 100,000 went on to march against the Axis forces — in what would eventually lead to the successful Allied invasion of western Europe occupied by Nazi Germany.

Planning for the D-Day invasion began as early as December 1941, when Dwight D. Eisenhower was appointed to the war plans division of the U.S. Army to design a plan for an Allied victory. In December 1943, Joseph Stalin and Franklin D. Roosevelt insisted on a May 1944 invasion at an inter-Allied conference in Tehran, Iran.

In January 1944, Eisenhower became the commander of the Supreme Headquarters Allied Expeditionary Force (SHAEF). Though May was the original target for the invasion, it was postponed due to difficulties with landing crafts; still, Eisenhower insisted on a unalterable June 5 date. Ultimately, weather issues pushed the date back a day to June 6. Eisenhower gave troops the order of that day as they prepared to invade the continent from the U.K.: "Full victory — Nothing else."

A series of historical photos detailing the famous Normandy invasion, some of which include graphic depictions of war, are below.

D-DAY 70th Anniversary

American soldiers crouching behind the bulkhead of a barge get ready to land for the Normandy Invasion in June of 1944.

Image: AP Photo/Associated Press

General beachhead area in Normandy, France, showing U.S. troops and equipment on the move, on June 11, 1944.

Image: AP Photo/Associated Press

Sitting in the cover of their foxholes, American soldiers of the Allied Expeditionary Force secure a beachhead during initial landing operations at Normandy, France, June 6, 1944.

Image: Weston Haynes/Associated Press

An anonymous American soldier, who died in combat during the Allied invasion, lies on the beach of the Normandy coast, in the early days of June 1944.

Image: AP Photo/Associated Press

Marauders of the 9th Air Force bombardment group fly over units of the Allied fleet as they approach landfall on the French coast on June 21, 1944.

Image: AP Photo/Associated Press

With his hair matted, and a weary but determined look in his face, this American soldier has his hand bandaged by a fellow medical officer, after he was wounded in battle in the early days of the Allied invasion of Normandy, France, in June 1944.

Image: AP Photo/Associated Press

British troops, trucks and ambulances stand on deck in readiness as the transport ship nears the coast of France, during the Allied invasion of the Normandy on June 8, 1944.

Image: AP Photo/Associated Press

American reinforcements arrive on the beaches of Normandy from a Coast Guard landing barge on the French coast on June 23, 1944.

Image: U.S. COAST GUARD/Associated Press

An unidentified Allied landing craft of, right, burns just off the shore somewhere on the north coast of France on June 6, 1944 during the invasion.

Image: AP Photo/Associated Press

Airmen of the Airborne Forces were among the first landings made in France during the Normandy invasions on June 6, 1944.

Image: AP Photo/Associated Press

Wounded British troops from the South Lancashire and Middlesex regiments are being helped ashore at Sword Beach, during the D-Day invasion of German occupied France during World War II on June 6, 1944.

Image: British Navy/Associated Press

General Dwight Eisenhower gives the order of the day, "Full Victory - Nothing Else," to paratroopers somewhere in England just before they board their planes to participate in the first assault in the invasion of the continent of Europe on June 6, 1944.

Image: U.S. Army Signal Corps Photo/Associated Press

Men and assault vehicles storm the beach as Allied landing crafts reach their destination during the initial Normandy landing operations in France on June 6, 1944.

Image: AP Photo/Associated Press

Members of an American landing unit help their exhausted comrades ashore during the Normandy invasion on June 6, 1944.

Image: International News Photo Pool/Associated Press

A soldier’s helmet tops the wooden cross with an inscription written in French on this grave of an American soldier made by French civilians in France on June 18, 1944.

Image: AP Photo/Associated Press

In Piccadilly Circus, crowds of Londoners read the first news of the invasion in the editions of the evening papers on June 6, 1944.

Image: AP Photo/Associated Press

U.S. Navy men take apart a German "Beetle," a miniature tank loaded with explosives, during the Allied Normandy landings in France in June 1944.

Image: AP Photo/Associated Press

Young Field Marshal Erwin Rommel headed Germany's Army Group B, on the coast hit by the Allied invasion, on June 6, 1944.

Image: AP Photo/Associated Press

American paratroopers proudly display a captured Nazi flag after they made a successful landing behind the German lines on the Normandy coast of France on June 9, 1944.

Image: AP Photo/Associated Press

Two Royal Air Force officers are presented with flowers by French children in France on June 10, 1944.

Image: AP Photo/Associated Press

American and German soldiers who paid for the invasion of France with their lives lie on the French ground covered with sheets, awaiting burial on June 12, 1944.

Image: Acme/Brandt/Associated Press

German soldiers come over the crest of a hill with their hands over their heads in surrender to American troops during the battle for the Normandy beachhead in France on June 11, 1944.

Image: AP Photo/Associated Press

Carrying their shoes and with their trousers rolled above their knees, a group of German prisoners stand on the beach of Normandy on June 14, 1944 waiting for transportation to England by landing craft.

Image: AP Photo/Associated Press

Allied casualties injured in the battles for the French beachhead lie on litters across the deck of a landing craft on June 17, 1944.

Image: AP Photo/Associated Press

Ducks (amphibious trucks) follow foot troops ashore during the World War II opening invasion of France by Allied forces on a 100-mile front along the Normandy coast on June 6, 1944.

Image: U.S. Coast Guard/Associated Press

America soldiers, equipped with full pack and extra allotments of ammunition, march down an English street to their invasion craft for embarkation on June 6, 1944.

Image: AP Photo/Associated Press

A little French girl finds three admirers from the ranks of American forces who have made a speedy and successful advance through Normandy, France on June 22, 1944.

Image: AP Photo/Associated Press

Pfc. Jerry Casillo, of Buffalo, N.Y., cleans his rifle during a rare moment of rest while his fellow soldiers catch some sleep on a beachhead at Normandy, France, during the Allied invasion on June 15, 1944.

Image: AP Photo/Associated Press

American troops follow in the tracks of tanks as they march along the beach during Allied Normandy landing operations in France, on June 9, 1944.

Image: Peter Carroll/Associated Press

Royal Air Force planes, towing gliders, are silhouetted in the light of dawn on D-Day over the English Channel on June 13, 1944.

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